Nadia starts counting at 49, and she counts by threes. If 49 is the 1st number that Nadia counts. what is the 9th number that she counts?
Answer: What is the first number that she counts? $49$ What is the second number that she counts? $\begin{align*}&49 + 3 \\ &= 52\end{align*}$ What is the third number that she counts? $\begin{align*}&49 + 3 + 3 \\ &= 49 + (2 \times 3) \\ &= 55\end{align*}$ What is the 9th number that she counts? $\begin{align*}&49 + (8\times3) \\ &= 49 + 24 \\ &= 73\end{align*}$